1. Field of the Invention
The present invention relates to a locking construction and more particularly to a locking construction for holding two electrical components such as a relay and a junction box or a relay box connected with each other. The locking construction allows engagement of the two electrical components to each other to be reliably and efficiently performed; prevents the two electrical components from being engaged with each other incompletely; and prevents the connection performance between the two electrical components from being deteriorated by external forces or vibrations applied thereto.
2. Description of the Related Arts
FIG. 1 shows an example of a locking construction for locking a relay 2 to a relay box 1.
Each terminal-accommodating chamber 3a is formed in a housing 3 of the relay box 1 and accommodates female terminals 4.
The relay 2 comprises a cylindrical engaging portion 2a which can fit around the housing 3 of the relay box 1. A pair of male terminals 5 is projectingly formed inside the engaging portions 2a.
In connecting the relay 2 with the relay box 1, the housing 3 is inserted into the engaging portion 2a of the relay 2 so as to press the male terminals 5 into the female terminals 4. The relay 2 is locked to the relay box 1 by contact pressure between the male terminals 5 and the female terminals 4.
In the construction for locking the relay 2 to the relay box 1 by only the contact pressure between the male terminals 5 and the female terminals 4, when an operator engages the relay 2 with the housing 3 of the relay box 1, the operator feels a resistance force in pressing the male terminal 5 into the female terminals 4. However, there is no mechanism to allow the operator to feel that the operator has pressed the relay 2 to the predetermined position. In addition, a locking sound is not generated when the relay 2 has engaged the relay box 1 completely. Thus, it is necessary for the operator to visually check whether the relay 2 has engaged the relay box 1 completely. Hence, it is difficult to perform an engaging operation efficiently.
There is also a possibility that the operator may terminate the engaging operation, with the relay 2 not completely engage with the relay box 1 because of the above-described reason.
Further, even though the relay 2 is in complete engagement with the relay box 1, there is a possibility that the relay 2 and the relay box 1 become disengaged from each other. That is, the capability of keeping the connection between the relay 2 and the relay box 1 deteriorates when external forces or vibrations are applied to the relay 2 and the relay box 1 connected with each other by only the contact pressure between the male terminals 5 and the female terminals 4.